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101.
Coronavirus infection (COVID-19) is a considerably dangerous disease with a high demise rate around the world. There is no known vaccination or medicine until our time because the unknown aspects of the virus are more significant than our theoretical and experimental knowledge. One of the most effective strategies for comprehending and controlling the spread of this epidemic is to model it using a powerful mathematical model. However, mathematical modeling with a fractional operator can provide explanations for the disease's possibility and severity. Accordingly, basic information will be provided to identify the kind of measure and intrusion that will be required to control the disease's progress. In this study, we propose using a fractional-order SEIARPQ model with the Caputo sense to model the coronavirus (COVID-19) pandemic, which has never been done before in the literature. The stability analysis, existence, uniqueness theorems, and numerical solutions of such a model are displayed. All results were numerically simulated using MATLAB programming. The current study supports the applicability and influence of fractional operators on real-world problems.  相似文献   
102.
International Journal of Theoretical Physics - The original article has been corrected. The left image of Figure 3 was previously not correct.  相似文献   
103.
We experimentally designed dispersion-managed repeaterless transmission systems with a pre-compensation and post-compensation technique using multi-channel-chirped fiber Bragg gratings. The repeaterless transmission link supports a single channel(1548.51 nm) with a 10 Gbps repeaterless transmission system over 300 km standard single-mode fiber(SSMF). In the system design, two distributed Raman amplifiers(DRAs) were used to improve the signal level propagated along the 300 km SSMF. The co-propagating DRA provided 15 dB on–off gain and the counter-propagating produced 32 dB on–off gain at the signal wavelength. The experiment results show that the post-compensation configuration achieves an optimal performance with a bit error rate at 1 × 10~(-9).  相似文献   
104.
105.
Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder characterized by progressive muscle loss, leading to difficulties in movement. Mutations in the DMD gene that code for the protein dystrophin are responsible for the development of DMD disorder, where the synthesis of this protein is completely halted. Therefore, circulating dystrophin protein could be a promising biomarker of DMD disease. Current methods for diagnosing DMD have sensitivity, specificity, and reproducibility limitations. Herein, a quantitative liquid chromatography–tandem spectrometry (LC–MS/MS) technique in multiple reaction monitoring (MRM) mode was designed and validated for accurate dystrophin protein measurement in a dried blood spot (DBS). The method was successfully validated on the basis of international guidelines regarding calibration curves, precision, and accuracy. In addition, patients and healthy controls were used to test the amount of dystrophin protein circulating in DBS samples as a potential biomarker for DMD disorders. DMD patients were found to have considerably lower levels than controls. To the best of our knowledge, this is the first study to report dystrophin levels in DBS through LC–MS/MS as a diagnostic marker for DMD to the proposed MRM method, providing a highly specific and sensitive approach to dystrophin quantification in a DBS that can be applied in DMD screening.  相似文献   
106.
The steam ejector is valuable and efficient in the fire suppression field due to its strong fluid-carrying capacity and mixing ability. It utilizes pressurized steam droplets generated at the exit to extinguish the fire quickly and the steam droplet strategy allows for an expressive decrease in water consumption. In this regard, the fire suppression process is influenced by the steam ejector efficiency, the performance of the pressurized steam, and the ejector core geometry, which controls the quality of the extinguishing mechanisms. This study investigated the impact of different mixing section diameters on the pumping performance of the ejector. The results showed that change in the diffuser throat diameter was susceptible to the entrainment ratio, which significantly increased, by 4 mm, by increasing the throat diameter of the diffuser and improved the pumping efficiency. Still, the critical back pressure of the ejector reduced. In addition, the diameter effect was studied and analyzed to evaluate the ejector performance under different operating parameters. The results revealed a rise in the entrainment ratio, then it diminished with increasing primary fluid pressure. The highest entrainment ratio recorded was 0.5 when the pressure reached 0.36 MPa at the critical range of back pressure, where the entrainment ratio remained constant until a certain back pressure value. Exceeding the critical pressure by increasing the back pressure to 7000 Pa permitted the entrainment ratio to reduce to zero. An optimum constant diameter maximized the ejector pumping efficiency under certain operating parameters. In actual design and production, it is necessary to consider both the exhaust efficiency and the ultimate exhaust capacity of the ejector.  相似文献   
107.
Due to the rise in awareness of global warming, many attempts to increase efficiency in the automotive industry are becoming prevalent. Design optimization can be used to increase the efficiency of electric vehicles by reducing aerodynamic drag and lift. The main focus of this paper is to analyse and optimise the aerodynamic characteristics of an electric vehicle to improve efficiency of using computational fluid dynamics modelling. Multiple part modifications were used to improve the drag and lift of the electric hatchback, testing various designs and dimensions. The numerical model of the study was validated using previous experimental results obtained from the literature. Simulation results are analysed in detail, including velocity magnitude, drag coefficient, drag force and lift coefficient. The modifications achieved in this research succeeded in reducing drag and were validated through some appropriate sources. The final model has been assembled with all modifications and is represented in this research. The results show that the base model attained an aerodynamic drag coefficient of 0.464, while the final design achieved a reasonably better overall performance by recording a 10% reduction in the drag coefficient. Moreover, within individual comparison with the final model, the second model with front spitter had an insignificant improvement, limited to 1.17%, compared with 11.18% when the rear diffuser was involved separately. In addition, the lift coefficient was significantly reduced to 73%, providing better stabilities and accounting for the safety measurements, especially at high velocity. The prediction of the airflow improvement was visualised, including the pathline contours consistent with the solutions. These research results provide a considerable transformation in the transportation field and help reduce fuel expenses and global emissions.  相似文献   
108.
The important role of Lactiplantibacillus plantarum strains in improving the human mucosal and systemic immunity, preventing non-steroidal anti-provocative drug-induced reduction in T-regulatory cells, and as probiotic starter cultures in food processing has motivated in-depth molecular and genomic research of these strains. The current study, building on this research concept, reveals the importance of Lactiplantibacillus plantarum 13-3 as a potential probiotic and bacteriocin-producing strain that helps in improving the condition of the human digestive system and thus enhances the immunity of the living beings via various extracellular proteins and exopolysaccharides. We have assessed the stability and quality of the L. plantarum 13-3 genome through de novo assembly and annotation through FAST-QC and RAST, respectively. The probiotic-producing components, secondary metabolites, phage prediction sites, pathogenicity and carbohydrate-producing enzymes in the genome of L. plantarum 13-3 have also been analyzed computationally. This study reveals that L. plantarum 13-3 is nonpathogenic with 218 subsystems and 32,918 qualities and five classes of sugars with several important functions. Two phage hit sites have been identified in the strain. Cyclic lactone autoinducer, terpenes, T3PKS, and RiPP-like gene clusters have also been identified in the strain evidencing its role in food processing. Combined, the non-pathogenicity and the food-processing ability of this strain have rendered this strain industrially important. The subsystem and qualities characterization provides a starting point to investigate the strain’s healthcare-related applications as well.  相似文献   
109.
110.
Molecular crystals of π-conjugated molecules are of great interest as the highly ordered dense packing offers superior charge and exciton transport compared with its amorphous counterparts. However, integration into optoelectronic devices remains a major challenge owing to its inherently brittle nature. Herein, control over the mechanical conformity in single crystals of pyridine-appended thiazolothiazole derivatives is reported by modulating the molecular packing through interaction engineering. Two polymorphs were prepared by achieving control over the thermodynamic/kinetic factors of crystallization; one of the polymorphs exhibits elastic bending whereas the other is brittle. The control over the bending ability was achieved by forming co-crystals with hydrogen/halogen bond donors. A seamless extended crisscross pattern with respect to the bend plane through a ditopic hydrogen-bonding motif showed the highest compliance towards mechanical bending, whereas the co-crystals with a layered crisscross arrangement with segregated layers of co-formers exhibit slightly lower bending conformity. These results update the rationale behind the plastic/elastic bending in molecular crystals. The co-crystals of ditopic halogen bond co-assemblies are particularly appealing for waveguiding applications as the co-crystals blend high mechanical flexibility and luminescence properties. The hydrogen bonded co-crystals are non-emissive in nature owing to excited state proton transfer dynamics. The rationale behind the fluorescence properties of these materials was also established from DFT calculations in a quantum mechanics/molecular mechanics (QM/MM) framework.  相似文献   
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